Further evidence for a relatively high sea level during the penultimate interglacial: open-system U-series ages from La Marina (Alicante, East Spain)

Abstract

The elevation and timing of high sea stands during Oxygen Isotope Stage (OIS) 7 are not as well constraíned as those of OIS 5e. Conflictíng values are reported from Medíterranean coastlines, and fossil dating is inaccurate because of ubiquitous open U-series systems. New morphostratigraphic data from La Marina (eastem Spain) supported by open-system U-series coral ages shed light on the maximum sea level duríng OIS 7. Fossil corals (Cladocora Caespitosa) underlying an OIS 5e marine unít yielded U-series ages from 178 ± (0 to 208 ± 1) ka (± 20σ n=7) with an outlier al 240 ± 18 ka. Mean open-system limit ages of 170 ± 10 (minimum age after correction for 234Th-230Th uptake) and 237 ± 20 ka (maximum ase after correction for 238U - 234U uptake) were calculated to have a probable age closer to the minimum value, for an assignment of OlS 7a or 7c. The occurrence of a warn-water "Senegalese" fauna (Strombus bubonius) in OIS5e and OIS 7 marine units confirms the arrival of tropical species to the Mediterranean before the last interglacial periodo Morpho-sedimentological and neotectonic studies suggest that the maximum paleo-sea level during OIS 7c or 7a was a few melers below that of OlS Se.